The Prevention and Treatment of Intestinal Failure-associated Liver Disease in Neonates and Children

An Overview of Short-Bowel Syndrome in Pediatric Patients: Focus on Clinical Management and Prevention of Complications

Short-bowel syndrome (SBS) in pediatric age is defined as a malabsorptive state, resulting from congenital malformations, significant small intestine surgical resection or disease-associated loss of absorption. SBS is the leading cause of intestinal failure in children and the underlying cause in 50% of patients on home parental nutrition. It is a life-altering and life-threatening disease due to the inability of the residual intestinal function to maintain nutritional homeostasis of protein, fluid, electrolyte or micronutrient without parenteral or enteral supplementation. The use of parenteral nutrition (PN) has improved medical care in SBS, decreasing mortality and improving the overall prognosis. However, the long-term use of PN is associated with the incidence of many complications, including liver disease and catheter-associated malfunction and bloodstream infections (CRBSIs). This manuscript is a narrative review of the current available evidence on the management of SBS in the pediatric population, focusing on prognostic factors and outcome. The literature review showed that in recent years, the standardization of management has demonstrated to improve the quality of life in these complex patients. Moreover, the development of knowledge in clinical practice has led to a reduction in mortality and morbidity. Diagnostic and therapeutic decisions should be made by a multidisciplinary team that includes neonatologists, pediatric surgeons, gastroenterologists, pediatricians, nutritionists and nurses. A significant improvement in prognosis can occur through the careful monitoring of nutritional status, avoiding dependence on PN and favoring an early introduction of enteral nutrition, and through the prevention, diagnosis and aggressive treatment of CRSBIs and SIBO. Multicenter initiatives, such as research consortium or data registries, are mandatory in order to personalize the management of these patients, improve their quality of life and reduce the cost of care.

Exclusive Fish Oil Lipid Emulsion Rescue Strategy Improves Cholestasis in Neonates on Partially Fish Oil-Based Lipid Emulsion: A Pilot Study

Resolution of parenteral nutrition-associated liver disease has been identified in infants receiving SMOFlipid™ or a 100% fish oil lipid emulsion (FOLE). However, the effect of FOLE is unknown when the previous emulsion received is a mixed lipid emulsion containing fish oil. This observational pilot study reports data regarding the use of Omegaven™ after the diagnosis of cholestasis while receiving SMOFlipid™. We conducted a retrospective review of medical charts of neonates in which a partially fish oil-based lipid emulsion was replaced by a fish oil lipid emulsion at 1 g/kg/day due to cholestasis. Thirty-eight infants (92.1% preterm, being 44.7% born below 28 weeks' gestation), received FOLE. Birth weight was 1390 (743.0; 2298) grams. The age that cholestasis diagnosed was 15.0 (10.0; 24.8) days. The fish oil emulsion was administered for 38.5 (11.2; 51.8) days. In 73.7% (28/38) of the neonates, the cholestasis was resolved. In 34.2% (13/38), resolution happened before FOLE discontinuation. In addition, in the rest of the neonates (15) in whom cholestasis resolved, resolution occurred after FOLE discontinuation. Nine of the neonates died. In conclusion, the use of a 100% fish oil-based emulsion in neonates afflicted with cholestasis developed while on a partially fish oil-based emulsion is associated with a bilirubin decrease.

Early detection of liver fibrosis with serum Mac-2 binding protein glycosylation-modified isomer (M2BPGi) during follow-up intestinal failure patients without intestinal failure-associated liver disease (IFALD)

PURPOSE

Mac-2 binding protein glycosylation-modified isomer (M2BPGi) is a new marker for hepatic fibrosis progression. We examined the relationship between serum M2BPGi levels and liver histological findings in intestinal failure (IF) patients without IF-associated liver disease (IFALD).

METHODS

This study included IF patients without IFALD followed at our hospital. All patients underwent routine liver biopsies per protocol every 1-2 years. We examined M2BPGi levels and histological findings in relation to aspartate aminotransferase (AST) to platelet ratio index, fibrosis-4 index, and AST/ALT ratio. Liver fibrosis was evaluated based on the METAVIR score.

RESULTS

Total 18 liver biopsies out of eight patients were included. The median age was 11.5 years. Mean M2BPGi was 0.44 cutoff index (COI) in patients with F0 fibrosis, 0.78 COI in patients with F1 fibrosis and 1.63 COI in patients with F2 fibrosis. Mean M2BPGi was significantly higher in patients with F2 versus F1 or F0 fibrosis (P < 0.016 and P < 0.028, respectively). M2BPGi levels were more strongly correlated with fibrosis stage than with other conventional fibrosis markers.

CONCLUSION

Serum M2BPGi is a novel marker of liver fibrosis in patients with IF. It is useful for follow-up prior to IFALD. Serum M2BPGi levels can support the interpretation of liver status.

Pediatric Smoflipid Therapy: Patient Response and Safety Concerns

BACKGROUND

Intestinal failure-associated liver disease (IFALD) occurs in ≤85% of neonates receiving prolonged parenteral nutrition. Strategies for treatment of IFALD include alternative lipid therapies, such as Smoflipid (Fresenius Kabi). In this study, we reviewed our institutional Smoflipid use, including predictors of patient response and safety concerns.

METHODS

This is a retrospective chart review of all pediatric patients who received Smoflipid therapy over a 2-year period at Riley Hospital for Children. Forty-two patients (89%) had cholestasis at the start of Smoflipid therapy and were included in group analysis. We compared patients based on response to Smoflipid therapy, identifying associations and predictors of patient response. We also documented patient safety concerns, including essential fatty acid deficiency (EFAD), rapid infusion, and compatibility/access issues.

RESULTS

Sixteen patients (38%) with cholestasis had resolution with Smoflipid. Those patients with resolution were older at initiation (58 vs 33.5 days; P = .010), treated with Smoflipid for longer (85.5 vs 41 days; P = .001), and had lower direct bilirubin at the start of Smoflipid therapy (3.7 vs 5.2 mg/dL; P = .035). We identified multiple safety concerns, including EFAD (54%), rapid infusion (17%), and missed doses (51%). No patient characteristics were found to correlate with Smofllpid therapy and diagnosis of EFAD.

CONCLUSION

In our patient population, Smoflipid therapy led to cholestasis resolution in patients with lower direct bilirubin or less-severe IFALD. Use of Smoflipid is also associated with significant safety concerns, and its use should be coupled with close monitoring in pediatric patients, particularly in neonates.

Exogenous Secretin Improves Parenteral Nutrition-associated Liver Disease in Rats

OBJECTIVES

Intestinal failure-associated liver disease (IFALD) is a feared and life-threatening complication in neonates with intestinal failure (IF) receiving long-term total parenteral nutrition (TPN). This study aims to investigate the effect of exogenous secretin on liver pathology and hepatic function in a rat model of PN-associated liver disease (PNALD).

METHODS

Male Sprague-Dawley rats underwent right jugular venous catheterization to receive 14-day continuous TPN therapy. All rats were allocated into 3 groups: the Control group (n = 8) did not have surgery or TPN and was fed standard rat chow ad libitum; the TPN group (n = 8) underwent catheter insertion and TPN treatment; and the TPN/S group (n = 8) also underwent catheter insertion, TPN treatment, and exogenous secretin treatment (2.5 nmol · kg · day) daily. Fourteen days after initial surgery, we collected the animals' liver and blood samples for further test.

RESULTS

The TPN/S group had diminished direct bilirubin (TPN, 2.1 ± 0.7 μmol/L; TPN/S, 1.5 ± 0.2 μmol/L) and liver total bile acid levels (TPN, 144.5 ± 21.2 μmol/L; TPN/S, 123.4 ± 10.4 μmol/L) and improved histological outcomes compared with those in the TPN group. Exogenous secretin also enhanced the canalicular transporter (BSEP, 0.5-fold, P = 0.011) and inhibited the basolateral transporter (OSTA, -0.48-fold, P = 0.002; OSTB, -0.6-fold, P = 0.013) of liver bile acid.

CONCLUSIONS

In this animal model of PNALD, secretin may improve cholestasis by enhancing canalicular transport, inhibiting the basolateral export of liver bile acid, and eventually decreasing the total bile acid level in the liver. Exogenous secretin treatment may potentially prevent and treat IFALD in IF patients relying on long-term TPN therapy.

Prevention and Treatment of Intestinal Failure-Associated Liver Disease in Children

Intestinal failure-associated liver disease (IFALD) is a threatening complication for children on long-term parenteral nutrition because of intestinal failure. When progressive and intractable, it may jeopardize intestinal rehabilitation and lead to combined liver and intestinal transplantation. The institution of dedicated intestinal failure centers has dramatically decreased the incidence of such complication. IFALD may rapidly fade away if very early management aimed at preventing progression to end-stage liver disease is provided. In this review, we address the etiology and risk factors of IFALD in order to introduce pillars of prevention (nutritional management and catheter-related infections control). The latest evidence of therapeutic strategies, such as medical and surgical treatments, is also discussed.

p38α MAPK antagonizing JNK to control the hepatic fat accumulation in pediatric patients onset intestinal failure

The p38α mitogen-activated protein kinase (MAPK) has been related to gluconeogenesis and lipid metabolism. However, the roles and related mechanisms of p38α MAPK in intestinal failure (IF)-associated liver steatosis remained poor understood. Here, our experimental evidence suggested that p38α MAPK significantly suppressed the fat accumulation in livers of IF patients mainly through two mechanisms. On the one hand, p38α MAPK increased hepatic bile acid (BA) synthesis by upregulating the expression of the rate-limiting enzyme cholesterol 7-α-hydroxylase (CYP7A1) and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), which in turn activated the transcription of the CYP7A1. On the other hand, p38α MAPK promoted fatty acid (FA) β-oxidation via upregulating peroxisome proliferator-activated receptor alpha (PPARα) and its transcriptional target genes carnitine palmitoyltransferase 1A (CPT1A) and peroxisomal acyl-coenzyme aoxidase 1 (ACOX1). Dual luciferase assays indicated that p38α MAPK increased the transcription of PPARα, PGC-1α and CYP7A1 by upregulating their promoters’ activities. In addition, in vitro and in vivo assays indicated p38α MAPK negatively regulates the hepatic steatosis by controlling JNK activation. In conculsion, our findings demonstrate that hepatic p38α MAPK functions as a negative regulator of liver steatosis in maintaining BA synthesis and FAO by antagonizing the c-Jun N-terminal kinase (JNK).

Outcomes from a 12-Week, Open-Label, Multicenter Clinical Trial of Teduglutide in Pediatric Short Bowel Syndrome

OBJECTIVE

To determine safety and pharmacodynamics/efficacy of teduglutide in children with intestinal failure associated with short bowel syndrome (SBS-IF).

STUDY DESIGN

This 12-week, open-label study enrolled patients aged 1-17 years with SBS-IF who required parenteral nutrition (PN) and showed minimal or no advance in enteral nutrition (EN) feeds. Patients enrolled sequentially into 3 teduglutide cohorts (0.0125 mg/kg/d [n = 8], 0.025 mg/kg/d [n = 14], 0.05 mg/kg/d [n = 15]) or received standard of care (SOC, n = 5). Descriptive summary statistics were used.

RESULTS

All patients experienced ≥1 treatment-emergent adverse event; most were mild or moderate. No serious teduglutide-related treatment-emergent adverse events occurred. Between baseline and week 12, prescribed PN volume and calories (kcal/kg/d) changed by a median of -41% and -45%, respectively, with 0.025 mg/kg/d teduglutide and by -25% and -52% with 0.05 mg/kg/d teduglutide. In contrast, PN volume and calories changed by 0% and -6%, respectively, with 0.0125 mg/kg/d teduglutide and by 0% and -1% with SOC. Per patient diary data, EN volume increased by a median of 22%, 32%, and 40% in the 0.0125, 0.025, and 0.05 mg/kg/d cohorts, respectively, and by 11% with SOC. Four patients achieved independence from PN, 3 in the 0.05 mg/kg/d cohort and 1 in the 0.025 mg/kg/d cohort. Study limitations included its short-term, open-label design, and small sample size.

CONCLUSIONS

Teduglutide was well tolerated in pediatric patients with SBS-IF. Teduglutide 0.025 or 0.05 mg/kg/d was associated with trends toward reductions in PN requirements and advancements in EN feeding in children with SBS-IF.

TRIAL REGISTRATION

ClinicalTrials.gov:NCT01952080; EudraCT: 2013-004588-30.

Predictors of failure of fish-oil therapy for intestinal failure-associated liver disease in children

BACKGROUND

Parenteral fish-oil (FO) therapy is a safe and effective treatment for intestinal failure-associated liver disease (IFALD). Patients whose cholestasis does not resolve with FO may progress to end-stage liver disease.

OBJECTIVE

We sought to identify factors associated with the failure of FO therapy in treating IFALD to guide prognostication and referral guidelines.

DESIGN

Prospectively collected data for patients treated with FO at Boston Children's Hospital from 2004 to 2014 were retrospectively reviewed. Resolution of cholestasis was defined as sustained direct bilirubin (DB) <2 mg/dL, and treatment failure as liver transplantation or death while DB was >2 mg/dL as of July 2015. Demographics, laboratory values, and medical history at FO therapy initiation were compared between patients who achieved resolution of cholestasis and those who failed therapy.

RESULTS

Among 182 patients treated with FO, 86% achieved resolution of cholestasis and 14% failed therapy. Patients who failed therapy had median (IQR) lower birth weight [1020 g (737, 1776 g) compared with 1608 g (815, 2438 g); P = 0.03] and were older at FO initiation [20.4 wk (9.9, 38.6 wk) compared with 11.7 wk (7.3, 21.4 wk); P = 0.02] than patients whose cholestasis resolved. Patients who failed therapy had more advanced liver disease at therapy initiation than patients whose cholestasis resolved, as evidenced by lower median (IQR) γ-glutamyltransferase [54 U/L (41, 103 U/L) compared with 112 U/L (76, 168 U/L); P < 0.001], higher DB [10.4 mg/dL (7.5, 14.1 mg/dL) compared with 4.4 mg/dL (3.1, 6.6 mg/dL); P < 0.001], and a higher pediatric end-stage liver disease (PELD) score [22 (14, 25) compared with 12 (7, 15); P < 0.001]. A PELD score of ≥15, history of gastrointestinal bleeding, age at FO initiation ≥16 wk, presence of nongastrointestinal comorbidities, and mechanical ventilation at FO initiation were independent predictors of treatment failure.

CONCLUSIONS

Most infants with IFALD responded to FO therapy with resolution of cholestasis, and liver transplantation was rarely required. Early FO initiation once biochemical cholestasis is detected in parenteral nutrition-dependent patients is recommended. This trial was registered at clinicaltrials.gov as NCT00910104.

Macrophage colony-stimulating factor (CSF1) controls monocyte production and maturation and the steady-state size of the liver in pigs

Macrophage colony-stimulating factor (CSF1) is an essential growth and differentiation factor for cells of the macrophage lineage. To explore the role of CSF1 in steady-state control of monocyte production and differentiation and tissue repair, we previously developed a bioactive protein with a longer half-life in circulation by fusing pig CSF1 with the Fc region of pig IgG1a. CSF1-Fc administration to pigs expanded progenitor pools in the marrow and selectively increased monocyte numbers and their expression of the maturation marker CD163. There was a rapid increase in the size of the liver, and extensive proliferation of hepatocytes associated with increased macrophage infiltration. Despite the large influx of macrophages, there was no evidence of liver injury and no increase in circulating liver enzymes. Microarray expression profiling of livers identified increased expression of macrophage markers, i.e., cytokines such as TNF, IL1, and IL6 known to influence hepatocyte proliferation, alongside cell cycle genes. The analysis also revealed selective enrichment of genes associated with portal, as opposed to centrilobular regions, as seen in hepatic regeneration. Combined with earlier data from the mouse, this study supports the existence of a CSF1-dependent feedback loop, linking macrophages of the liver with bone marrow and blood monocytes, to mediate homeostatic control of the size of the liver. The results also provide evidence of safety and efficacy for possible clinical applications of CSF1-Fc.

ESPGHAN Committee on Nutrition Position Paper. Intravenous Lipid Emulsions and Risk of Hepatotoxicity in Infants and Children: a Systematic Review and Meta-analysis

The aim of the present article was to perform a systematic review with meta-analysis of available scientific evidence regarding the role of different intravenous lipid emulsions (ILE) in the pathogenesis of cholestasis and parenteral nutrition-associated liver disease. A systematic review of the literature (up to March 2015) identified 23 randomized controlled trials (RCTs). Of these, 17 were performed in preterm infants or critically ill neonates with a short duration of intervention, 2 in older children with short-term use (following surgery or bone marrow transplantation), 1 in neonates with long-term use, and 3 in infants and children receiving long-term parenteral nutrition (PN). Meta-analysis showed no differences in the rate of cholestasis or bilirubin levels associated with short-term use of different ILEs. Because of high heterogeneity of the long-term studies no meta-analysis could be performed. Available studies found that the use of multicomponent fish oil (FO)-containing ILE compared with pure soya bean oil (SO), ILE-reduced liver enzymes, and bilirubin levels in noncholestatic children on long-term PN and one other RCT found that FO-based ILE-reversed cholestasis in a proportion of patients. The ESPGHAN Committee on Nutrition concludes that there is no evidence of a difference in rates of cholestasis or bilirubin levels between different ILE for short-term use in neonates. The use of multicomponent FO-containing ILE may contribute to a decrease in total bilirubin levels in children with IF on prolonged PN. Well-designed RCTs are, however, lacking and long-term effects have not been determined.

Normal Growth and Essential Fatty Acid Status in Children With Intestinal Failure on Lipid Limitation

OBJECTIVES

Lipid limitation, that is, ≤1 g · kg⁻¹ · day⁻¹ of soy oil lipid emulsion (SOLE), has been suggested as a method to reduce the risk of intestinal failure (IF)-associated liver disease (IFALD). There are limited data as to the effects of this strategy on growth and essential fatty acid (EFA) status. The aim of the study was to assess growth, prevalence of cholestasis, and EFA deficiency in patients with IF who were provided daily SOLE at a dose ≤1 g · kg⁻¹ · day⁻¹.

METHODS

Medical records were retrospectively reviewed from 9 patients age 16 months to 8 years who had IF requiring parenteral nutrition support for >12 months. Parenteral nutrition supplied a mean of 53% of total energy (range 24%-86%).

RESULTS

Mean SOLE dose was 0.61 g · kg⁻¹ · day⁻¹ (range 0.4-0.81 g · kg⁻¹ · day⁻¹). After 1 month of lipid limitation between 2011 and 2014, no patient developed IFALD as defined by a direct bilirubin >2 mg/dL. The median direct bilirubin was 0.1 mg/dL (range 0.075-0.85 mg/dL). No patient developed EFA deficiency as defined by a triene-to-tetraene ratio >0.2 (median 0.026, range 0.017-0.076). Height z scores increased from mean of -2.568 (range -10.8 to 0.878) to -0.484 (range -3.546 to 0.822). Weight z scores increased from mean of -1.412 (range -5.871 to 0.906) to -0.595 (range -2.178 to 0.926).

CONCLUSIONS

In this case series, lipid limitation allowed normal growth while preventing the development of cholestasis and EFA deficiency.

Effect of an Olive Oil-Based Lipid Emulsion Compared With a Soybean Oil-Based Lipid Emulsion on Liver Chemistry and Bile Acid Composition in Preterm Infants Receiving Parenteral Nutrition: A Double-Blind, Randomized Trial

BACKGROUND

The pathogenesis of parenteral nutrition (PN)-associated liver dysfunction is multifactorial. Lipid emulsions may be one of the putative mechanisms. Our aim was to comparatively assess the effect of parenteral olive oil- and soybean oil-based lipid emulsions on liver chemistry and bile acid composition in preterm infants.

METHODS

We performed a double-blind, randomized clinical study in which 103 preterm infants were randomly assigned to PN using either soybean oil-based lipid emulsion (SO; n = 51) or olive oil (OO)-based lipid emulsion (OO; n = 52). The primary end point was liver chemistry. The secondary end point was the plasma bile acid composition.

RESULTS

One hundred infants completed this study. In the SO group, the serum direct bilirubin was significantly higher after PN for 7 days compared with the OO group. Bile acids increased over time in both treatment groups. However, specific differences in the change in bile acid composition over time were noted between groups.

CONCLUSIONS

Differences in direct bilirubin and bile acid composition were observed over time between the 2 groups. Considering the long-term use of lipid emulsions in higher risk babies, these findings might be useful for understanding the pathogenesis of PN-associated liver dysfunction.

Glutamine-supplemented parenteral nutrition and probiotics in four adult autoimmune enteropathy patients

To evaluate the effects of glutamine-supplemented parenteral nutrition (PN) and probiotics in adult autoimmune enteropathy (AIE) patients. Four adult AIE patients were identified from April 2006 to January 2012. Clinical and nutritional data were obtained from the patients' medical records. Glutamine-supplemented PN started immediately when the AIE diagnosis was confirmed. The total PN duration was 351 days. According to the PN prescription, the average caloric intake ranged from 20 to 25 kcal/kg/day, and the protein intake ranged from 1.2 to 1.5 g/kg/day. Alanyl-glutamine (20 g/day) was administered to AIE patients for 4 weeks followed by a 2-week break, and this treatment schedule was repeated when PN lasted for more than 6 weeks. Body weight gain and an increased serum albumin level were achieved after PN, and defecation frequency and quality also improved. Each patient received oral supplements, 250 mL of Ensure and two probiotics capsules (each capsule containing 0.5×108 colonies) three times a day when enteral nutrition started. Three AIE patients were successfully weaned off PN, and one patient died of pneumonia. Glutamine-supplemented PN and probiotics show promise in managing patients with AIE and related malnutrition.

Risks and benefits of prophylactic cyclic parenteral nutrition in surgical neonates

BACKGROUND

Cyclic parenteral nutrition (PN) is used for both the treatment and prevention of parenteral nutrition-associated liver disease (PNALD). Early initiation of prophylactic cyclic PN may not be well tolerated in young neonates. Our objective was to test the hypothesis that prophylactic cyclic PN initiated prior to the onset of hyperbilirubinemia is associated with younger age at initiation, lower bilirubin levels, and similar rates of adverse events compared to therapeutic cyclic PN initiated after established cholestasis in surgical neonates.

METHODS

A retrospective review of infants with gastrointestinal disorders requiring surgical intervention who received cyclic PN 2006-2011 was performed.

RESULTS

Of the 43 infants eligible for analysis, 23 received prophylactic and 20 received therapeutic cyclic PN. Infants in both groups were comparable in demographics, surgical diagnoses, and illness severity. At initiation of cyclic PN, infants with prophylactic cyclic PN were significantly younger in chronologic (P = .003) and postmenstrual age (P = .029). Prophylactic cyclic PN was associated with a significantly lower incidence of hyperbilirubinemia (P = .001), lower maximum conjugated bilirubin (P < .0001), and lower last checked conjugated bilirubin (P = .032) compared to the therapeutic cyclic PN. The incidence of hypoglycemia, hyperglycemia, and hypertriglyceridemia was similar for the 2 groups.

CONCLUSIONS

There may be a potential benefit to initiating cyclic PN prior to the development of hyperbilirubinemia in surgical neonates. Early initiation of prophylactic cyclic PN does not appear to increase the risk for adverse events.

The gut-liver axis

PURPOSE OF REVIEW

The liver adaptively responds to extra-intestinal and intestinal inflammation. In recent years, the role of the autonomic nervous system, intestinal failure and gut microbiota has been investigated in the development of hepatic, intestinal and extra-intestinal disease.

RECENT FINDINGS

The autonomic nervous system can be stimulated via enteral fat leading to cholecystokinin release, stimulating receptors in the gut and in the brain. This promotes bowel integrity, dampening the inflammatory response to food antigens. Consensus exists that intravenously administered long-chain fatty acids can cause liver damage but randomized-controlled trials are lacking. Disruption of the enterohepatic circulation of bile salts can give rise to cholestasis and nonalcoholic fatty liver disease, which may progress to fibrosis and cirrhosis. Reduced intestinal availability of bile salts reduces stimulation of the farnesoid X receptor. This may induce hepatic bile salt overload and associated hepatotoxicity through reduced action of intestinal fibroblast growth factor 19. Evidence is put forward to suggest that the intestinal microbiota is associated with liver abnormalities.

SUMMARY

Enteral lipids reduce inflammation and liver damage during stress or systemic inflammation, whereas parenteral lipid is associated with liver damage. Maintaining the enterohepatic circulation of bile salts limits hepatic cholestasis through an farnesoid X receptor feedback pathway. Changes in gut microbiota composition may induce liver disease.

Aspartate aminotransferase to platelet ratio index correlates with hepatic cirrhosis but not with fibrosis in pediatric patients with intestinal failure

BACKGROUND AND OBJECTIVES

Patients with intestinal failure (IF) require parenteral nutrition (PN) support to obtain enough nutrients to sustain growth; long-term PN use is associated with significant liver damage. The aim of this study was to analyze the use of a noninvasive test, the aspartate aminotransferase to platelet ratio index (APRI), in the diagnosis of liver disease in pediatric patients with IF.

METHODS

Medical records of all Boston Children's Hospital patients who received PN and underwent a liver biopsy from January 2006 until November 2010 were reviewed. Patients with IF with a clinical diagnosis were selected. APRI was calculated as (aspartate aminotransferase [U/L]/upper normal limit) × 100/platelets (10(9) cells/L). Presence of fibrosis and cirrhosis was estimated using the METAVIR score in liver biopsies.

RESULTS

Sixty-two liver biopsies from 48 patients (22 girls) were studied. Mean APRI values in the different METAVIR categories (0-1, 2-3, 4) were 1.80, 1.17, and 4.24, respectively (analysis of variance P = 0.053; Bonferroni test for cirrhosis vs fibrosis P = 0.048). APRI could significantly predict cirrhosis (odds ratio 1.2; 95% confidence interval [CI] 1.001-1.43) but not fibrosis (METAVIR 2-3, odds ratio 1.00; 95% CI 0.86-1.18). Area under the receiver operating characteristic curve for cirrhosis was 0.67 (95% CI 0.45-0.89; P = 0.13).

CONCLUSIONS

APRI, a noninvasive, easy-to-obtain bedside test, significantly predicts cirrhosis but not fibrosis in pediatric patients with IFALD. Because the clinicians need a noninvasive test to differentiate among different stages of liver fibrosis rather than differentiating cirrhosis from normal, we cannot recommend the use of this test in pediatric patients with IFALD for this purpose.

Effect of decreased parenteral soybean lipid emulsion on hepatic function in infants at risk for parenteral nutrition-associated liver disease: a pilot study

PURPOSE

We performed a pilot trial to compare reduced dose versus standard soybean lipid emulsion in neonates at risk for parenteral nutrition-associated liver disease.

METHODS

A prospective randomized controlled trial was performed (2009-2011) enrolling surgical patients ≥ 26 weeks' gestation anticipated to require >50% of daily caloric intake from parenteral nutrition (PN) for at least 4 weeks. Randomization occurred into either reduced (1.0 g/kg/day) or standard (3g/kg/day) groups. Co-primary outcomes for interpretation of the results were conjugated bilirubin and total bile acids. Additional outcomes included ALT, AST, GGT, alkaline phosphatase, growth, and essential fatty acid levels. Outcomes were compared between treatment groups using Wilcoxon rank sums tests.

RESULTS

Twenty-eight patients (47% enrollment rate) were included in the study with an average treatment duration of 5.4 weeks. Groups had similar PN calories and protein intake throughout the study. Total increase from baseline was smaller in the reduced vs. standard group for conjugated bilirubin (p=0.04) and total bile acids (p=0.02). Weight z-score increased more in the standard group, and no patient experienced essential fatty acid deficiency.

CONCLUSION

Markers of cholestasis rose at a slower rate using reduced lipid doses. This pilot study demonstrates feasibility and need for a larger study evaluating the effects of reduced lipids in patients at risk for developing parenteral nutrition-associated liver disease.

Fish oil-based lipid emulsion in the treatment of parenteral nutrition-associated liver disease

PURPOSE OF REVIEW

Parenteral nutrition-associated liver disease (PNALD) is a major cause of morbidity and mortality in the parenteral nutrition-dependent population. Here, we review the most recent literature involving a fish oil-based lipid emulsion (FOLE) and its effects on PNALD.

RECENT FINDINGS

Vegetable oil-based lipid emulsions (VBLEs) contribute to PNALD. This may be due to parenteral phytosterols and/or the presence of pro-inflammatory mediators. Whereas a small reduction in the dose of VBLE does not appear to prevent PNALD, a significant reduction in the dose may reverse PNALD; however, it carries the risk of essential fatty acid deficiency. Furthermore, the impact of extreme lipid restriction on subsequent neurodevelopment is unknown. Combination lipid emulsions containing fish oil are associated with decreased bilirubin levels, though no studies compare these emulsions with the outcomes with FOLE alone. The utility of FOLE in the reversal of PNALD has been demonstrated and its administration does not lead to essential fatty acid deficiency. Furthermore, there is evidence that FOLE may prevent PNALD.

CONCLUSION

FOLE appears to be an efficacious treatment to reverse PNALD. However, more studies are necessary to determine if FOLE might also be beneficial in the prevention of PNALD. Future studies should additionally focus on the preterm infant population, as they represent a major population requiring parenteral nutrition support for survival.

Pathogenesis and treatment of parenteral nutrition-associated liver disease

BACKGROUND

Parenteral nutrition-associated liver disease (PNALD) has been common in patients who require long-term parenteral nutrition. PNALD develops in 40%-60% of infants on long-term parenteral nutrition compared with 15%-40% of adults on home parenteral nutrition for intestinal failure. The pathogenesis of PNALD is multifactorial and remains unclear. There is no specific treatment. Management strategies for its prevention and treatment depend on an understanding of many risk factors. This review aims to provide an update on the pathogenesis and treatment of this disease.

DATA SOURCES

A literature search was performed on the MEDLINE and Web of Science databases for articles published up to October 2011, using the keywords: parenteral nutrition associated liver disease, intestinal failure associated liver disease, lipid emulsions and fish oil. The available data reported in the relevant literatures were analyzed.

RESULTS

The literature search provided a huge amount of evidence about the pathogenesis and management strategies on PNALD. Currently, lack of enteral feeding, extended duration of parenteral nutrition, recurrent sepsis, and nutrient deficiency or excess may play important roles in the pathogenesis of PNALD. Recent studies found that phytosterols, present as contaminants in soy-based lipid emulsions, are also an important factor in the pathogenesis. Moreover, the treatment of PNALD is discussed.

CONCLUSIONS

The use of lipid emulsions, phytosterols in particular, is associated with PNALD. Management strategies for the prevention and treatment of PNALD include consideration of early enteral feeding, the use of specialized lipid emulsions such as fish oil emulsions, and isolated small bowel or combined liver and small bowel transplantation. A greater understanding of the pathogenesis of PNALD has led to promising interventions to prevent and treat this condition. Future work should aim to better understand the mechanisms of PNALD and the long-term outcomes of its treatment.

The use of fish oil lipid emulsion in the treatment of intestinal failure associated liver disease (IFALD)

Since 2004, fish oil based lipid emulsions have been used in the treatment of intestinal failure associated liver disease, with a noticeable impact on decreasing the incidence of morbidity and mortality of this often fatal condition. With this new therapy, however, different approaches have emerged as well as concerns about potential risks with using fish oil as a monotherapy. This review will discuss the experience to date with this lipid emulsion along with the rational for its use, controversies and concerns.

Enteral nutrients potentiate glucagon-like peptide-2 action and reduce dependence on parenteral nutrition in a rat model of human intestinal failure

Glucagon-like peptide-2 (GLP-2) is a nutrient-dependent, proglucagon-derived gut hormone that shows promise for the treatment of short bowel syndrome (SBS). Our objective was to investigate how combination GLP-2 + enteral nutrients (EN) affects intestinal adaption in a rat model that mimics severe human SBS and requires parenteral nutrition (PN). Male Sprague-Dawley rats were assigned to one of five groups and maintained with PN for 18 days: total parenteral nutrition (TPN) alone, TPN + GLP-2 (100 μg·kg(-1)·day(-1)), PN + EN + GLP-2(7 days), PN + EN + GLP-2(18 days), and a nonsurgical oral reference group. Animals underwent massive distal bowel resection followed by jejunocolic anastomosis and placement of jugular catheters. Starting on postoperative day 4, rats in the EN groups were allowed ad libitum access to EN. Groups provided PN + EN + GLP-2 had their rate of PN reduced by 0.25 ml/day starting on postoperative day 6. Groups provided PN + EN + GLP-2 demonstrated significantly greater body weight gain with similar energy intake and a safe 80% reduction in PN compared with TPN ± GLP-2. Groups provided PN + EN + GLP-2 for 7 or 18 days showed similar body weight gain, residual jejunal length, and digestive capacity. Groups provided PN + EN + GLP-2 showed increased jejunal GLP-2 receptor (GLP-2R), insulin-like growth factor-I (IGF-I), and IGF-binding protein-5 (IGFBP-5) expression. Treatment with TPN + GLP-2 demonstrated increased jejunal expression of epidermal growth factor. Cessation of GLP-2 after 7 days with continued EN sustained the majority of intestinal adaption and significantly increased expression of colonic proglucagon compared with PN + EN + GLP-2 for 18 days, and increased plasma GLP-2 concentrations compared with TPN alone. In summary, EN potentiate the intestinotrophic actions of GLP-2 by improving body weight gain allowing for a safe 80% reduction in PN with increased jejunal expression of GLP-2R, IGF-I, and IGFBP-5 following distal bowel resection in the rat.

Provision of a soy-based intravenous lipid emulsion at 1 g/kg/d does not prevent cholestasis in neonates

BACKGROUND

One of the most common and severe complications of long-term parenteral nutrition (PN) is PN-associated cholestasis. The soybean oil-based lipid emulsion administered with PN has been associated with cholestasis, leading to an interest in lipid reduction strategies. The purpose of this study was to determine whether the provision of a soybean oil-based lipid emulsion at 1 g/kg/d compared with 2-3 g/kg/d is associated with a reduced incidence of cholestasis.

METHODS

Retrospective review of neonates admitted between 2007 and 2011 with a gastrointestinal condition necessitating ≥ 21 days of PN support. Neonates were divided into 2 groups based on the intravenous lipid emulsion dose: 1-g group (1 g/kg/d) and 2- to 3-g group (2-3 g/kg/d). The primary outcome measure was the incidence of cholestasis.

RESULTS

Sixty-one patients met inclusion criteria (n = 29, 1-g group; n = 32, 2- to 3-g group). The 2 groups did not differ in any baseline characteristics other than associated comorbidities that were more common in the 2- to 3-g group. The duration of PN, the number of operative procedures and bloodstream infections, and enteral nutrition (EN) were similar between groups. The incidence of cholestasis was not different between groups (51.7%, 1-g group; 43.8%, 2- to 3-g group; P = .61), and there was no difference between groups in the time to cholestasis (32.6 ± 24.1 days, 1-g group; 27.7 ± 10.6 days, 2- to 3-g group; P = .48). Overall, 44.8% of patients with cholestasis were transitioned to full EN, and 55.2% were transitioned to a fish oil-based lipid emulsion after which the direct bilirubin normalized in all patients.

CONCLUSION

Lipid reduction to 1 g/kg/d does not prevent or delay the onset of cholestasis in neonates.

Continuous parenteral and enteral nutrition induces metabolic dysfunction in neonatal pigs

BACKGROUND

We previously showed that parenteral nutrition (PN) compared with formula feeding results in hepatic insulin resistance and steatosis in neonatal pigs. The current aim was to test whether the route of feeding (intravenous [IV] vs enteral) rather than other feeding modalities (diet, pattern) had contributed to the outcome.

METHODS

Neonatal pigs were fed enterally or parenterally for 14 days with 1 of 4 feeding modalities as follows: (1) enteral polymeric formula intermittently (FORM), (2) enteral elemental diet (ED) intermittently (IEN), (3) enteral ED continuously (CEN), and (4) parenteral ED continuously (PN). Subgroups of pigs underwent IV glucose tolerance tests (IVGTT) and hyperinsulinemic-euglycemic clamps (CLAMP). Following CLAMP, pigs were euthanized and tissues collected for further analysis.

RESULTS

Insulin secretion during IVGTT was significantly higher and glucose infusion rates during CLAMP were lower in CEN and PN than in FORM and IEN. Endogenous glucose production rate was suppressed to zero in all groups during CLAMP. In the fed state, plasma glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide (GLP)-1, and GLP-2 were different between feeding modalities. Insulin receptor phosphorylation in liver and muscle was decreased in IEN, CEN, and PN compared with FORM. Liver weight was highest in PN. Steatosis and myeloperoxidase (MPO) activity tended to be highest in PN and CEN. Enterally fed groups had higher plasma GLP-2 and jejunum weight compared with PN.

CONCLUSIONS

PN and enteral nutrition (EN) when given continuously as an elemental diet reduces insulin sensitivity and the secretion of key gut incretins. The intermittent vs continuous pattern of EN produced the optimal effect on metabolic function.